LM340K-5.0 Linear Voltage Regulator

Part Overview

The LM340K-5.0 is a linear voltage regulator IC from Texas Instruments designed for positive fixed output applications. This device delivers a regulated 5V output at up to 1.5A, making it suitable for power management applications requiring stable DC voltage conversion. The part is currently in active production status with 3700 units available in stock. Alternative part numbers exist within the same product family to accommodate different procurement channels and packaging specifications.

Substiute Parts

LM340K-5.0

Texas InstrumentsIn Stock: 3772LM340K-5.0 Datasheet

Current PartRFQ

LM340K-5.0/NOPB

Texas InstrumentsIn Stock: 1196LM340K-5.0/NOPB Datasheet

Parametric EquivalentRFQ

Key Parameters

Substitute Part Grouping Explanation

The LM340K-5.0/NOPB is a parametric equivalent of the LM340K-5.0. Substitution eligibility is determined by matching the following critical parameters:

• Output voltage specification: 5V fixed
• Output current capability: 1.5A
• Input voltage maximum rating: 35V
• Voltage dropout characteristic: 2V @ 1A
• Quiescent current: 6 mA
• PSRR performance: 70dB (120Hz)
• Protection features: Over Current and Short Circuit protection
• Package configuration: TO-204AA, TO-3
• Mounting technology: Through Hole
• Operating temperature range: 0°C to 125°C
• Regulatory compliance: ROHS3 Compliant

Both parts share the same base product number (LM340) and are manufactured by Texas Instruments. The difference in part number designation reflects packaging and distribution channel variations rather than functional or electrical differences.

Parameter Comparison

Engineering Selection Recommendations

Both the LM340K-5.0 and LM340K-5.0/NOPB are active production parts from Texas Instruments with full ROHS3 compliance and REACH unaffected status. Selection between these parts should be based on procurement availability and supply chain requirements. The LM340K-5.0 currently has 3700 units in stock, while the LM340K-5.0/NOPB variant has 1145 units available. Both parts meet identical electrical and mechanical specifications and are suitable for direct substitution in applications requiring a 5V, 1.5A linear regulator with TO-3 packaging.

Frequently Asked Questions (FAQ)

Q: Can LM340K-5.0/NOPB be used as a direct replacement for LM340K-5.0?

A: Yes. Both parts are parametrically equivalent with identical electrical characteristics, output specifications, protection features, and package configurations. They are interchangeable for circuit design purposes.

Q: What does the "/NOPB" designation indicate?

A: The "/NOPB" suffix indicates a packaging or distribution channel variation. It does not affect the functional or electrical performance of the device.

Q: Are there any differences in compliance or certifications between these parts?

A: No. Both parts carry identical RoHS3 compliance, REACH unaffected status, and MSL ratings. They meet the same regulatory requirements.

Q: Can these parts be used interchangeably in PCB designs?

A: Yes. Both parts use the same TO-3 package with identical pinout and mounting requirements. No PCB layout modifications are necessary when substituting between these part numbers.

Q: What is the significance of the 2V dropout voltage specification?

A: The 2V dropout voltage at 1A output current defines the minimum input voltage required to maintain regulation at full load. For a 5V output, the input voltage must be at least 7V under these conditions.

Q: Are these parts suitable for high-temperature applications?

A: Both parts are rated for operation from 0°C to 125°C. Applications requiring operation outside this range require alternative device selection.